Largest-ever genetic study of personality finds 1,260 DNA variants tied to traits

The largest genetic investigation of personality ever conducted has identified 1,260 genetic variants associated with the Big Five personality traits, but researchers stress that DNA is far from destiny — environment still does most of the heavy lifting in shaping who we are.

The study, published Wednesday in Nature by the Revived Genomics of Personality Consortium, combined personality and genetic data from 46 research cohorts encompassing roughly 1.14 million people. Participants completed questionnaires measuring the Big Five traits — openness to experience, conscientiousness, extraversion, agreeableness, and neuroticism — and provided DNA samples that researchers then scanned for variants linked to personality differences.sciencealert+1

Small Effects, Big Numbers

Of the 1,260 variants identified, 824 had never previously been linked to personality. But lead author Ted Schwaba of Michigan State University was quick to temper expectations.english.elpais+1

"There is no single 'personality gene,'" Schwaba said in a statement. "Personality traits are associated with many genetic variants, but even the largest effects of individual genetic variants are still very small."medicalxpress

How small? One variant linked to extraversion might shift a person from the 50th to the 50.35th percentile. Across all traits, the genetic variants captured by the study accounted for roughly 4.8 to 9.3 percent of variation in each personality trait. When researchers used genetic data to predict personality in separate groups, they could explain less than 4 percent of individual differences.sciencealert+2

"If we'd want to know someone's personality at an individual level, genetics isn't really a fruitful path; we can simply measure personality and get a very clear picture, genes wouldn't add anything there," co-senior author Michel Nivard of the University of Bristol told ScienceAlert.sciencealert

Beyond Personality

Where the findings gain broader relevance is in their connections to life outcomes. The genetic variants that predict personality also partially predict mental and physical health, longevity, education, and career paths. Variants linked to extraversion were associated with heightened COVID-19 infection risk during the early pandemic, likely reflecting greater social contact. Variants tied to openness predicted that individuals would move to more cosmopolitan neighborhoods, which in turn may reinforce the trait.miragenews+3

The researchers also confirmed, by comparing siblings and fraternal twins, that these genetic effects were not simply byproducts of shared upbringing.sciencealert

Genes as a Starting Point

Despite the scale of the findings, the message from researchers was consistent: genetics offers population-level insight, not individual prophecy.

"I would hate for people to come away thinking that genetics set their personality in stone, or that their individual personality is measurable via their genome," Nivard said. "If you want to know more about your personality relative to others, take one of the many free tests online, and you'll learn so much more!"sciencealert